Anthropic Overtakes OpenAI in U.S. Business Adoption for the First Time, Ramp Data Shows

For the first time since the generative-AI boom began, more U.S. businesses are paying for Anthropic than for OpenAI. According to the latest Ramp AI Index, Anthropic’s business adoption climbed 3.8 percentage points in April to 34.4%, edging past OpenAI, whose share slipped 2.9 points to 32.3%. It is the first time the two have swapped positions — a crossover few in the industry predicted even a year ago.

The figures come from Ramp, the corporate-card and finance-automation platform, which builds the index from actual corporate-card and invoice payments across more than 70,000 businesses and roughly $100 billion in annual spend. Because it tracks money that companies actually commit rather than survey responses or sign-ups, the index is widely read as a proxy for paid, sticky enterprise usage rather than free experimentation.

The scale of the reversal is the real story. Over the past twelve months Anthropic quadrupled its business adoption, rising from under 8% to today’s 34.4%, while OpenAI’s share grew just 0.3% over the same stretch. Much of Anthropic’s momentum has been credited to Claude’s strength with developers — Claude Code in particular — and to a string of large enterprise deployments that have turned pilots into company-wide rollouts.

Overall AI adoption among the businesses Ramp tracks now sits at 50.6%, meaning the two leaders are fighting over a market that is still expanding quickly. That growth cuts both ways: a rising tide has lifted Anthropic fastest, but it also leaves room for rivals — and for OpenAI — to claw back share as buying patterns shift.

Analysts are quick to caution that the lead is fragile. Three pressures, in particular, could erase it: incentives that push providers toward more expensive, higher-margin models that enterprises may resist; episodic reliability and performance complaints as usage scales; and Anthropic’s own recent pricing changes, which have moved some customers toward usage-based billing and raised effective costs. Any one of them could slow the adoption curve that just carried Anthropic into the lead.